Studies of pesticide exposures[unreadable] The Agricultural Health Study is a large, prospective cohort study of pesticide applicators and spouses from Iowa and North Carolina. Investigators completed several pesticide-specific analysis, examining the association of cancer and exposures to alachlor, atrazine and chlorpyrifos. Investigators found a significantly increasing trend for incidence of all lymphohematopoietic cancers (n=135) associated with lifetime exposure-days and intensity-weighted exposure-days to alachlor, and a significant increasing trend for incidence of lung cancers associated with chlorpyrifos lifetime exposure-days and with intensity-weighted exposure-days. An analysis of 309 incident breast cancer cases observed an SIR of 0.87 (95% CI: 0.74, 1.02) for women who reported ever applying pesticides and 1.05 (95% CI: 0.89, 1.24) for women who reported never applying pesticides. There was some evidence of increased risk associated with use of 2,4,5-TP and possibly of dieldrin, captan, and 2,4,5-T, but small numbers of cases precluded firm conclusions.[unreadable] [unreadable] In a case-control study of NHL, 30 pesticides in dust from used vacuum cleaner bags were analyzed. Results were consistent with uses of pesticide products, and lent credibility to the use of questionnaire data and pesticide residues in carpet dust for assessing residential exposure.[unreadable] [unreadable] Radiation studies[unreadable] Data from all North American studies of residential radon and lung cancer, with 3,662 cases and 4,966 controls, were pooled. Under a linear model, the OR at 100 Bq/m3 was 1.11 (95% CI: 1.00,1.28). Data were also pooled from two case-control studies of radon and lung cancer in China, including 1050 lung cancer cases and 1996 controls. The OR at 100 Bq/m3 was 1.13 (95% CI: 1.01,1.36). These estimates are compatible with extrapolations based on miner data, and provide direct evidence of an association between residential radon and lung cancer risk. [unreadable] [unreadable] Cancer mortality and incidence from protracted low-dose radiation exposure was evaluated in a large cohort of U.S. radiologic technologists. Risks increased for breast cancer, leukemia, and circulatory disease, especially stroke, for subjects working in early years when radiation exposure was likely highest. No consistent excess risk was found for multiple myeloma and lymphoma. Molecular studies were performed in subsets of the cohort. Using the kin-cohort design, investigators found that some variants in genes within the base-excision repair pathway (XRCC1) and BRCA1 interacting proteins (BRIP1) may play a role as low penetrance breast cancer risk alleles. In a study of DNA repair capacity measured by the alkaline single cell gel electrophoresis (comet) assay, the pattern of results suggests that increased endogenous DNA damage in proliferating cells may be a risk factor for breast and thyroid cancer and could contribute to the identification of susceptible sub-groups. The association between a SNP in the HER2 oncogene and breast cancer was also evaluated in female first-degree relatives of breast cancer probands. The cumulative RRs for the Val/Val genotype versus Ile/Ile and Ile/Val were 1.37 (95% CI: 0.00, 3.98) up to age 50 and 2.54 (95% CI: 0.40, 3.63) up to age 70, and support an elevated risk of breast cancer for women with the Val/Val genotype. [unreadable] [unreadable] Cancer risks among formaldehyde workers[unreadable] Analysis of mortality data from a cohort of 25,619 formaldehyde workers revealed exposure-response relationships for leukemia, particularly myeloid leukemia, and cancer of the nasopharynx, but no association with cancers of the pancreas, brain, lung or prostate. [unreadable] [unreadable] Oral cancer in Puerto Rico[unreadable] In a population-based case-control study in Puerto Rico, genotypes of CYP1A1, GSTM1, and GSTT1 were determined for 132 oral cancer patients and 143 control subjects. The null variant of GSTM1 was associated with a significant decrease in oral cancer risk (OR=0.6).